Explores the impact of diet on heart health through an experiment involving high school students. Participants are divided into two groups: one group follows a low-fat diet aimed at reducing cholesterol, while the other indulges in a high-fat diet. Over four weeks, the students learn how their dietary choices affect their cholesterol levels and overall heart health. The film emphasizes the importance of diet in preventing heart disease, particularly highlighting that poor eating habits can lead to serious health risks even at a young age.